PHILADELPHIA - Germany is seeking extradition of an 89-year-old Pennsylvania man in connection with the deaths of hundreds of thousands of Jewish men, women and children at Nazi concentration camps, a U.S. judge said on Wednesday.

Johann Breyer was arrested by U.S. authorities on Tuesday at his home in Philadelphia on allegations that he served as a Nazi SS guard at the Auschwitz and Buchenwald camps.

Germany has issued a warrant for his arrest, U.S. Magistrate Judge Timothy Rice said at Breyer's appearance in U.S. District Court in Philadelphia.

German authorities are charging him with aiding and abetting the deaths of 216,000 Jews, a figure arrived at by estimating the survival rate of prisoners packed into 158 trains that arrived at Auschwitz between May and October 1944, according to documents.

The retired tool-and-die maker, born in Czechoslovakia, joined the Waffen SS at age 17. He has argued that he was coerced into joining and was not involving in deaths at the camps.

The judge ordered him held without bail. Breyer's attorney tried unsuccessfully to argue he is not healthy enough to stay in federal detention while his case is being decided.

Breyer, wearing a baggy green jumpsuit and leaning on a cane, was asked if he understood what was happening. "Not really," he replied to the judge.

Breyer immigrated to the United States in 1952. He was the subject of deportation proceedings in the 1990s when his attorneys argued that he was a natural U.S. citizen because his mother was born in Philadelphia.

Newly discovered evidence has strengthened the case against Breyer, the New York Times reported. War-era records show he was at Auschwitz earlier than he has acknowledged and that he also served as a guard in a notorious subcamp, known as Birkenau, used exclusively to kill prisoners, the newspaper said.

Breyer served as an armed guard at Buchenwald before transferring in 1944 to Auschwitz where, according to court documents, he has said he served as a perimeter guard.

In the courtroom wrangling over Breyer's health, his grandson Greg Breyer testified that he had suffered strokes and had a heart condition. Assistant U.S. Attorney Andrea Foulkes countered that Breyer had renewed his driver's license two years ago and that he did not rely on home health aides.